Improvement in pans for backing electrotypes



UNITED STATES PATENT OFFICE.

w. ArLEeec, or QUEBEC, CANADA.

. Specification. forming part of Letters Patent No. $9,410, dated August 4, 1h63.

To all whom it may concern:

Be it known that I, W. A..LEGGQ, of Quebec, in the Province of Canada, have invented a new and useful Improvement in Pans for Backing Electrotypes; and I do hereby de,

clare that the following is a full, clear, and-ex# act description of the same, reference 'being had to 'the accompanying drawings; forming a part of this specification, in which- Figure l representsa plan or top view of my invention. Fig. 2 isa longitudinal vertical section of the same.

`Similar letters of reference in. both views 1udicate corresponding parts. l

For the purpose ot backing electrotypes two styles lof pans 'aensed atpresent, one known as the open, and the other as the closed pan. With the open pan sound plates can be produced; but it is impossible either to` deter'- miue the correct thickness ofthe plate or to guard it against distortion of face by shrinkage, there being .no gage to effect this purpose.` The closed pau is provided with a reliable gage to determine the-thickness ofthe plate;' but the metal cooling from the ends is liable to shrink in the middle, and an uneven and unsoundplate isv the result.

'The pan which forms the object of .the pres ent invention differs from the ordinary'clo'sed pan in that the interior or upper pan is perforated throughoutits surface with minute holes. The 'endattained by this smple contrivance is thatall inclination to shrinkage in the electrotype-plate proper, is done away-with,fas a consta-nt iowof liquid metal isv kept up fromthe upper to the lower plate until the lower plate solidiiies, the. metal contained in the upper pan being naturally the last tocool, andas'ound plate of a uniform thickness throughout is the result.

To enable those skilled iu the art to make and use my invention7 I will proceed to describe it with reference to the drawings.

Arepresents the outer pan, made-of cast-iron or any other suitable material, of suficient size and depth for. the occasion. The inner pan, B, is also made of cast'iron or other suitable material, and it tits into the pan A, be-

` ing retained in position by ribs c risiug'from the bottom of the pa'niA, -and by ribs b,pr o jecting downward from the bottom of the pan B and catching over the ends of the ribs-a of the pan A. GlampsfG/,which catch ovenlugs projecting from the* edges of the panv A,'jand which are providedywith set-screws@ to bear upon the edges of. the pan Bf, serve to secure the in-ner intheouter pan and to hold it firmly in. position'. By means of'theribs a' b an open space is'formed between the bottom of the pan A and that ot' the pan B to receive the shell and `to determine the thickness of the plate. It is obvious that by altering the height ot these 'ribs the thickness of the plate can be varied'as much as may be desired. The bottom of` .the inner pan, B, is perforated with a large number of holes, d, through which the liquid metal runs down" to the space between the bottom oftheitwopanse- The operation is as follows: The paus being placed in the liquid metal, first the upper and then the lower-are allowed t'o remain until the lower pan has attained the heat necessaryv to fuse the tin on the electrotype-shell. It is then withdrawn and placed upon a cooling,- slab. The shell previously tinned is placed thereon., the upper pan adjusted and secured in position by the clamps G or by any other equivalent means, and the metal poured into the upper. pan, the 1 nore quickly the better. From this pan the metal descends in a shower upon the electrotype-shell, pressing its-down equally at every point, thus obviating' the use ot' springs or Weighted wireSidwhich lare very tronble'somein theirapplict'ttio'n'.A The whole.-

is then allowed vto cool and the upper pan isdetached. Byaslight blowof a lnallet thel little'joints of metal bindi'ngtogether the sheet-4 of metal inthe upper and '.thatdn the lower' pan are broken, and the' electrotype-plate ,is released. It is perfectly backed up. being even on the face, equal in thickness alljover, and soundin texture. .lu this -way a' perfect sheet of metal is always obtained, even on its face, and of any desired thickness, doin g away entirely with the necessity ot' shaving and economizing largely in money and time. 'The frequent handling of the plate is obviated and a superior article is produced, as. the inbre an electrotypeplate is' handled the more it is liable to accidents.

The number and distribution of the hotes in the bottom of the inner pan is a matter of lit'- -tle moment, as the object, to be attainedis vthroughout its extent; Holes bored at interis, evenness of face, regularity in thickness,

and soundness of metal.

By providing thepans with 'proper gages..

the electrotype-shells may be at once backed up to the height of ordinary type, requiring nothing further than the trimming o f the edges to make them'ready for the printer.

What I claim as new, and desire to secure by Letters Patent, is-- 'lhe perforations or holes d in the bottoni of the inner pan, B, when the same is used, in combination with the outer pan, A, in the mauner and for the purpose substantially as herein shown and described.

WL A. LEGGO.

Witnesses:

RoB'r. H. SoULLlN, M. M LWINGsToN. 

